9
# I have 3 lists:
L1 = [1, 2, 3, 4, 5, 6, 7, 8, 9]
L2 = [4, 7, 8]
L3 = [5, 2, 9]
# I want to create another that is L1 minus L2's memebers and L3's memebers, so:
L4 = (L1 - L2) - L3 # Of course this isn't going to work
I'm wondering, what is the "correct" way to do this. I can do it many different ways, but Python's style guide says there should be only 1 correct way of doing each thing. I've never known what this was.